This is the only sub of its kind. Kicker introduces the world’s only square sub. 18 inches of boom is only meant to be used by the world’s most serious system fanatics. With an insane max wattage of 10,000 this sub is simply amazing. Because of its extreme power, Kicker had to manufacture something to power the beast of a sub. This amp is known as the Warhorse. The Solo X also comes with the patented “S.PA.IR.” technology to keep the heat down and the bass up. This is a subwoofer at its best.